Noncontact IC card, card reader/writer, and card system

摘要

The invention proposes a card reader/writer comprising a UART (13), which converts serial data into parallel data and vice versa; a send circuit (14), which modulates a digital signal of the serial data from said UART and converts it into a send electrical signal; a transmitting antenna (15B), which transmits said send electrical signal as a radio wave; a receiving antenna (16), which converts a received radio wave into a receive electrical signal; a receive circuit (17), which demodulates said receive electrical signal and converts it into a digital signal; and a control unit, which controls said card reader/writer, wherein said transmitting antenna (15B) comprises a series resonance circuit and said receiving antenna (16) comprises a parallel resonance circuit.